[makemeknowit]

First off, here's the plan for the ride:

'84 Bronco currently undergoing an EFI transplant with a 302 from a '93 F150, will remain basically stock until recieving a Kenne Bell, retaining the C6 that currently resides in the Bronco. GM corporate 14 bolt should arrive this week, Dana 60 front to follow. Will see about 20 miles a day street driving, unknown amount of offroading on the weekends. Will likely run 37-38" radials for street duty, 42s for playtime. Minimum lift, maximum sawzall action. A minimum of 4.88s with the possibility of 5.13s. Undecided on the gear vendor and steep gear route or backing off the gear a little, 4.11s or so, and running dual transfer cases. I ran a search for dual t-cases and didn't come up with anything. What would the cost differences and difficulty of install differences be? Or is the dual t-case route something best left to rockcrawlers? We won't be doing any crawling just lots of mudslinging, hill climbing, trail riding.....

Thanks
Mike

 

[Traveler]

Can't help much on the dual transfer cases, except it won't help you high power, or RPM's. Only the low range will be affected.

The gear vender, I know about those. Figure about a 800 RPM drop, or 28% less rpms. So if you go with 5.13 and end up at 3,200 rpm at 60 mph, the Gear vendor will drop it to around 2,300.
28% of 3200 is 896.
But the gear vender will only engage over 20 mph. so in off road it is useless. It is pretty much for Highway use only.

If I was going to use it as a daily driver, go for the gear vender. Watch Ebay you can get used ones for $1000.
Strictly off road, and I would go with a dual T case for the low rock crawling rev's.

You can't do both because your drive shaft would be like 24" long. That is the only reason you can't.

 

[plug ugly]

depending on ho much room you have, since the c6 has no od, I would run closer to 4.10 or 4.56 with that tire size and either run dual cases or a 1356 with a klune. 5.13 and no od would kill you on the road (in the neighborhood of around 3000rpm on the hiway, or higher)

Thats what I would do if I didnt have this e40d

 

[Zach94]

I would consider a crawler box, I have only seen a dual tcase in right outputs. The lower crawl would let you run a highway friendly gear and allow years to have a bigger, stronger pinion. This is probably not a big deal with a 14bolt, but you never know with 42's.

 

[Davids78Bronco]

The cost for the doubler Tcase will be lower than a Klune V, and both will have driveline modifications anyway

 

[Davids78Bronco]

i am going to go the 203 to 205 route here pretty soon on my 92. it should workout sweet!
the one thing with doing this though, you are rasiing your driveshaft failure rate up since there is much more torque goign through its U joints than before....

 

[Davids78Bronco]

Like Zach here, I'm planning a doubler for mine... I just need to see about getting the doubler's dimensions, and having someone cut down my 203's shaft

 

[TTBlows]

But the gear vender will only engage over 20 mph. so in off road it is useless. It is pretty much for Highway use only.

If we're speaking of the box I'm thinking of, it's worthless in 4wd for a more important reason: it hangs off the back of the t-case so it only OD's the rear driveshaft.

To the original question, I've gotta wonder if that 302 is gonna have the low end torque you want if you gear it high (ie 4.10 or whatever). I'd probably gear it deep and try to obtain an OD.

If you had a bigblock my answer would be exactly the opposite.

 

[SquattyD]

Gear vendors goes after the tcase, making your real dshaft real short. The 14 bolt doesnt have that high of a pinion, so the angles arent going to be that good. So I wouldnt go that route.


Off Road Design's Doubler is prob the most popular kit for the dual 203/205 setup. Looks pretty good, heard good things, but I hear fitment can be an issue, and its kinda pricey considering it doesnt come with shifters. Plus you have to get your own 203, plus rebuild costs. So the base price goes from about $800 to over $1k with shifters, and then the price of a 203 and rebuilding the 203.

Another option is the Klune V system. Bolts right in between your trans and tcase. Replaces your intermediary housing, and includes spacers for your application so that the tcase stays in the same place, and so do your driveshafts. They are about $2k, so if you got a couple hundred extra bucks, I think its worth it over the doubler.

And of course there is the vaunted Atlas. This will replace your entire transfer case. And depending on the gear range you select, they range in price from $1800 to $2200. Lightweight, gear driven, twin stick, a great buy if you have the cash.

So what would I do? If I was planning on spending over $1k on a doubler, I would wait awhile longer, save some more paychecks, and get the Atlas.

 

[Traveler]

If we're speaking of the box I'm thinking of, it's worthless in 4wd for a more important reason: it hangs off the back of the t-case so it only OD's the rear driveshaft.

Yep I didn't even remember that part, I am used to people saying they can split every gear, well you can't, unless your motor will hold 8,000 rpm.

 

[makemeknowit]

I didn't realize the Atlas was a twin stick, have to look into going that route.

Thanks

 

[TTBlows]

So what would I do? If I was planning on spending over $1k on a doubler, I would wait awhile longer, save some more paychecks, and get the Atlas.

You'd wind up with something that is only supported by Advance Adapters and gives you only one low range option. I'd take the doubler in a heartbeat, 2:1 or 4:1 .... or get the 3:1 kit for the 203 and your choices become 2:1, 3:1 or 4:1.

You can twin stick a 205. Atlases are for competition buggies IMO, doublers are for the average enthusiast trail rig.

 

[makemeknowit]

If we're speaking of the box I'm thinking of, it's worthless in 4wd for a more important reason: it hangs off the back of the t-case so it only OD's the rear driveshaft.

To the original question, I've gotta wonder if that 302 is gonna have the low end torque you want if you gear it high (ie 4.10 or whatever). I'd probably gear it deep and try to obtain an OD.

If you had a bigblock my answer would be exactly the opposite.

Only ODing the rear would be perfect since the whole reason for the vendor would be to take some of the bite out of 4.88/5.13s on the street. Offroad we'd want the max gearing. I've got an AOD (for sale now) but it's a 2WD trans, I asked here about running it after having it converted to 4WD status but the general concensus was the C6 would make an ass out of it in the strength dept.

 

[Blaze]

It will as an off-road rig, but I'm with Keith..and speaking from experience ('95 on 38.5's with 5:13's and OD tranny) I'd go 5:13's and use an OD tranny if you plan on DDing it....If it's gonna be trail only I'd prolly go even lower than 5:13's but thats just me..:shrug

 

[ultimatebronco]

You'd wind up with something that is only supported by Advance Adapters and gives you only one low range option. I'd take the doubler in a heartbeat, 2:1 or 4:1 .... or get the 3:1 kit for the 203 and your choices become 2:1, 3:1 or 4:1.

You can twin stick a 205. Atlases are for competition buggies IMO, doublers are for the average enthusiast trail rig.

Your choices would be 2:1, 3:1, and 6:1 :thumbup As soon as I can I'm going this route.

 

[tim330i]

You'd wind up with something that is only supported by Advance Adapters and gives you only one low range option. I'd take the doubler in a heartbeat, 2:1 or 4:1 .... or get the 3:1 kit for the 203 and your choices become 2:1, 3:1 or 4:1.

You can twin stick a 205. Atlases are for competition buggies IMO, doublers are for the average enthusiast trail rig.

I understand not wanting to be locked into Advance Adapters for parts (I assume expensive) if you get the Atlas case but isn't it supposed to be indestructible more or less? Plus as mentioned it is lighter.

Basically can you expand on why you think the doubler is better?

This a great thread, please keep it going

Tim

 

[Davids78Bronco]

Basically can you expand on why you think the doubler is better?

becuase a doubler is a 1/3 of the price, and you have a 2-1 gear ratio AND a 4-1. an atlas doesnt let you switch, plus you still have 1-1

 

[Traveler]

C'mon let's do some real custom work and put a T-18 between the C6 and the T-case.
That would be cool! Of course we might run onto drive shaft legnth issues again.

 

[Davids78Bronco]

C'mon let's do some real custom work and put a T-18 between the C6 and the T-case.
That would be cool! Of course we might run onto drive shaft legnth issues again.

i will lengthen my wheelbase out back if i have issues with my rear shaft and th ecombo im running.

 

[axaviere]

just to let you guys know, there is a vendor on POR that has his own design of doubler and its alot less than the ones that AA and ORU sell. take a look in the vendors section. also, isnt there a new lower gear thats available for the 205 &/or the 203? i think someone mentioned that. the doubler is what i am leaning towards myself, and i am looking at the one from the guy on POR. oh hey, David i think it was mentioned a guy taking the cases and clocking them so they were all above the bottom frame rail. made his own linkage & levers too.